<template>

  <div class="app-container">

    <h2 style="text-align: center;">发布新课程</h2>

    <el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">
      <el-step title="填写课程基本信息"/>
      <el-step title="创建课程大纲"/>
      <el-step title="提交审核"/>
    </el-steps>

    <el-form label-width="120px">

        <!-- 课程封面-->
        <el-form-item label="课程封面">
            <el-upload
                :show-file-list="false"
                :on-success="handleAvatarSuccess"
                :before-upload="beforeAvatarUpload"
                :action="BASE_API+'/eduoss/fileoss'"
                class="avatar-uploader">
                <img :src="courseInfo.cover">
            </el-upload>
        </el-form-item>

        <el-form-item label="课程标题">
            <el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课"/>
        </el-form-item>

        <!-- 所属分类：级联下拉列表 -->
        <!-- 一级分类 -->
        <el-form-item label="课程类别">
            <el-select
                v-model="courseInfo.subjectParentId"
                placeholder="一级分类"
                @change="getTwoSubjectList">
                <el-option
                v-for="subject in oneSubjectList"
                :key="subject.id"
                :label="subject.title"
                :value="subject.id"/>
            </el-select>
            <!-- 二级分类 -->
            <el-select v-model="courseInfo.subjectId" placeholder="二级分类">
                <el-option
                    v-for="subject in twoSubjectList"
                    :key="subject.id"
                    :label="subject.title"
                    :value="subject.id"/>
            </el-select>
        </el-form-item>

        <!-- 课程讲师 -->
        <el-form-item label="课程讲师">
            <el-select
                v-model="courseInfo.teacherId"
                placeholder="请选择">
                <el-option
                v-for="teacher in teacherList"
                :key="teacher.id"
                :label="teacher.name"
                :value="teacher.id"/>
            </el-select>
        </el-form-item>

        <el-form-item label="总课时">
            <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder="请填写课程的总课时数"/>
        </el-form-item>

        <!-- 课程简介 TODO -->
        <!-- 课程简介-->
        <el-form-item label="课程简介">
            <tinymce :height="300" v-model="courseInfo.description"/>
        </el-form-item>
        
        <el-form-item label="课程价格">
            <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder="免费课程请设置为0元"/> 元
        </el-form-item>

        <el-form-item>
            <el-button :disabled="saveBtnDisabled" type="primary" @click="next">保存并下一步</el-button>
        </el-form-item>
    </el-form>
  </div>
</template>
<script>
import course from '@/api/edu/course.js'
import subject from "@/api/edu/subject"
import Tinymce from '@/components/Tinymce'//副本编辑器组件
export default {
  components: { Tinymce },  
  data() {
    return {
      BASE_API: process.env.BASE_API,// 接口API地址       
      saveBtnDisabled: false, // 保存按钮是否禁用
      courseId:'',
      courseInfo:{
        title: '',
        subjectId: '',
        subjectParentId:'',
        teacherId: '',
        lessonNum: 0,
        description: '',
        cover: 'http://cdn.laowang.shop/touxiang',
        price: 0
      },
      teacherList:[],
      oneSubjectList:[],
      twoSubjectList:[]
    }
  },
  watch:{
    $route(to,from){
      this.init()
    }
  },
  created() {
    console.log('info created')
    this.init()
  },

  methods: {
    init(){
        if(this.$route.params && this.$route.params.id){
            this.courseId=this.$route.params.id
            this.getCourseInfo()
        }else{
            this.courseInfo={}
            this.courseId=""
        }
        this.findAll()//获取讲师列表
        this.getOneSubjectList()//获取课程分类
    },
    //获取回显课程信息
    getCourseInfo(){
        course.getCourse(this.courseId).then(res=>{
            this.courseInfo=res.data.courseInfo
            console.log('一级分类id',this.courseInfo.subjectParentId)
            console.log('二级分类id',this.courseInfo.subjectId)
            //遍历一级分类，判断id设置二级分类
            for(var i=0;i<this.oneSubjectList.length;i++){
                var oneSubject=this.oneSubjectList[i]
                if(this.courseInfo.subjectParentId == oneSubject.id){
                    this.twoSubjectList=oneSubject.children
                }
            }
        })       
    },  
    
    next() {
      console.log('next')
      if(!this.courseId){
          this.addCourse()
      }else{
          this.updateCourse()
      }
    },

    //添加课程信息
    addCourse(){
        course.addCourseInfo(this.courseInfo).then(res=>{
          this.$message({
            type: 'success',
            message: '添加课程基本信息成功!'
          })
          this.$router.push({ path: '/course/chapter/'+res.data.courseId})
      })
    },

    //修改课程信息
    updateCourse(){
        course.updateCourse(this.courseInfo).then(res=>{
            this.$message({
          type: 'success',
          message: '修改课程基本信息成功!'
          })
          this.$router.push({ path: '/course/chapter/'+this.courseId})
        })
    },
    //获取所有讲师
    findAll(){
        course.findAll().then(res=>{
            this.teacherList=res.data.list
        })
        console.log("教师列表",this.teacherList)  
    },

    //获取课程一级分类
    getOneSubjectList(){
        subject.getAllSubject().then(res=>{
            this.oneSubjectList=res.data.list
        })
    },

    //一级分类改变时获取二级分类
    getTwoSubjectList(id){
        this.courseInfo.subjectId=''//清空残余二级类型
        for(var i=0;i<this.oneSubjectList.length;i++){
            if(id==this.oneSubjectList[i].id){
                this.twoSubjectList=this.oneSubjectList[i].children
            }
        }
    },

    //上传成功
    handleAvatarSuccess(res, file) {
        console.log(res)// 上传响应
        this.courseInfo.cover = res.data.url
        console.log(this.courseInfo.cover)
    },

    //上传之前
    beforeAvatarUpload(file) {
        const isJPG = file.type === 'image/jpeg'
        const isLt2M = file.size / 1024 / 1024 < 2

        if (!isJPG) {
            this.$message.error('上传头像图片只能是 JPG 格式!')
        }
        if (!isLt2M) {
            this.$message.error('上传头像图片大小不能超过 2MB!')
        }
        return isJPG && isLt2M
    }
  }
}
</script>

<style scoped>
.tinymce-container {
  line-height: 29px;
}
</style>
